Make unused parameters unnamed
Make unused parameters unnamed

This way they cannot be used any more.

Shuts the compiler up for issue CURA-3137.

ROBO3D/CuraEngine,alephobjects/CuraEngine,ROBO3D/CuraEngine,alephobjects/CuraEngine,Ultimaker/CuraEngine,ROBO3D/CuraEngine,Ultimaker/CuraEngine,alephobjects/CuraEngine